Proteins are together with carbohydrats an fats forming the group of macronutrients. Proteins are essential for our body. They are made out of amino acids and are responsable for the construction of our body. Our body can synthesize some proteins itself but other it can not and it is important that we eat these proteins (amino acids) not to suffer from a deficiency. Eight amino acids our body can not synthesize and we need to eat products with these amino acids.
Not every protein can be used in our body very easily. The biological value of proteins says with which efficiency our body can incorporate the protein coming from the food. It defines how much of the amino acids can be used in the protein synthesis in our body. As much similar the protein is to the body’s protein the higher is the biological value, because our body can use this protein more efficient.
Many years ago it was thought that an egg has the best biological value of all foods. That is the reason why the egg now is considered as 100. By now it is known that several foods have a better biological value than an egg. The number will be higher if the biological value is better. If the number of a food (protein) is high, the need of this protein is smaller.
Even products with a small biological value can be very interesting in our nutrition because the biological value can be completed by two products with low biological values. If the amino acids of these to products do complete each other very well, the biological value is higher than the sum of the two biological values.
Animal proteins usually have a higher biological value than vegetable proteins because animals are more similar to us than plants. But as it is written above, the right combination of proteins makes the food more valuable. Examples are:
– Potato and egg
– Milk and wheatflour
– Beef and potato